Given a single machine and a set of jobs with due dates, the classical NP-hard problem of scheduling to minimize total tardiness is a well-understood one. Lawler gave an FPTAS for it some twenty years ago. If the jobs have positive weights the problem of minimizing total weighted tardiness seems to be considerably more intricate. In this paper, we give some of the first approximation algorithms...

The single machine total weighted tardiness problem (SMTWTP) is a well-known planning problem from operations research, engineering and computer science. It is characterized by the assignment of starting times for a given set of jobs on a single processor, minimizing the (weighted) tardy completion of the jobs with respect to given due dates. In this sense, the tardiness is given an economical ...

This paper concerns the single machine total weighted tardiness scheduling with sequence-dependent setup times, usually referred as 1|sij | ∑ wjTj . In this NP-hard problem, each job has an associated processing time, due date and a weight. For each pair of jobs i and j, there may be a setup time before starting to process j in case this job is scheduled immediately after i. The objective is to...

Many optimization problems in the industrial engineering world, particularly in manufacturing systems, are very complex in nature and difficult to solve by conventional optimization techniques. The use of formal approaches is frequently limited owing to the complexity of the models or algorithms. In this paper, a novel approach is proposed for large scale single machine weighted tardiness probl...

  This paper deals with minimization of tardiness in single machine scheduling problem when each job has two different due-dates i.e. ordinary due-date and drop dead date. The drop dead date is the date in which jobs’ weights rise sharply or the customer cancels the order. A linear programming formulation is developed for the problem and since the problem is known to be NP-hard, three heuristic...

We present a multi-agent variant of the Single Machine Total Weighted Tardiness Problem with Sequence-Dependent Setup Times. Since, i.a., agents have an incentive to lie, central planning is not feasible and decentralized methods such as automated negotiations are needed. Hereto, we propose and evaluate an iterative quota-based negotiation protocol.

This paper deals with the permutation flowshop scheduling problem time lags constraints to minimize total weighted tardiness criterion by using Branch and Bound algorithm. A new lower bound was developed for problem. The computational experiments indicate that proposed algorithm provides good solution in terms of quality requirements.

Job scheduling is concerned with the optimal allocation of scare resources with objective of optimising one or several criteria. Job scheduling has been a fruitful area of research for many decades in which scheduling resolve both allocation of machines and order of processing. If the jobs are scheduled properly, not only the time is saved but also efficiency of system is increased. The paralle...